clam trouble

[whatcaneyedo]

It looks like a Squamosa to me. Cleaner wrasse are often reported to pick on clam mantels. To rule that out completely you could isolate the two. Either place them in different tanks or build a cage around the clam. Have you checked the underside of it? My Squamosa was recently being bothered by a large number of bristle worms hiding underneath. Once most of the worms were removed it imediately went back to looking normal. I've also had clams pinch up like that when they were being attacked by pyram snails. Or it could be 'pinched mantel', a condition (pathogen?) that is often curable with a fresh water dip.

If you list things like your tank equipment, other inhabitants and all of your water chemistry parameters that often helps us troubleshoot.